Traces of blood in the urine: what It means and when to be concerned

10/02/2026

Discovering traces of blood in the urine, even if invisible to the naked eye, can be alarming. In medicine, this phenomenon is called microscopic hematuria when blood cells are detected only through laboratory tests, or macroscopic hematuria when the urine appears pink, red, or brown. But what does it really mean, and when should you see a doctor?

Common Causes of Blood in the Urine

Blood in the urine can have various origins, some benign and others more serious:

Urinary tract infections (UTIs)
Infections can irritate the lining of the bladder or urethra, causing small amounts of bleeding.

Kidney or bladder stones
Stones can scratch the walls of the urinary tract, causing blood in the urine, often accompanied by severe pain.

Trauma or physical exertion
Falls, blows, or intense physical exercise can cause temporary hematuria.

Kidney diseases
Conditions such as glomerulonephritis or other kidney diseases can lead to the presence of blood in the urine, sometimes without obvious symptoms.

Tumors of the urinary tract
Tumors of the bladder, ureter, or kidney can cause hematuria, often initially painless.

Medications and substances
Some medications (anticoagulants, anti-inflammatory drugs) or foods (like beets or large amounts of cranberries) can cause reddish urine or alter lab test results.

How Blood in the Urine is Detected

Traces of blood are often discovered during a routine urine test. The examination may include:

Chemical test: detects the presence of hemoglobin or red blood cells using test strips.
Microscopic examination: confirms the presence of red blood cells and, if necessary, distinguishes between glomerular and non-glomerular hematuria.

If the test is positive, the doctor may recommend further investigations, such as renal and bladder ultrasound, cystoscopy, or blood tests, to identify the cause.

Associated Symptoms Not to Ignore

Besides the presence of blood, it is important to pay attention to symptoms such as:

Lower back or abdominal pain
Burning during urination
Frequent need to urinate
Cloudy or foul-smelling urine
Fever or general malaise

The appearance of one or more of these symptoms requires prompt medical consultation.

When to See a Doctor

Even though hematuria is often linked to transient or benign causes, any episode of blood in the urine should be evaluated by a doctor. Early diagnosis is crucial, especially to rule out more serious problems like kidney stones or urinary tract tumors.

Conclusion

The discovery of traces of blood in the urine is not a diagnosis in itself but a signal that requires attention. With modern diagnostic tools and proper follow-up, most causes can be identified and successfully treated.